Carbonated candy is a hard candy containing carbon dioxide gas as disclosed in U.S. Pat. No. 3,012,893 which is herein incorporated by reference. Such a candy is made by the process which comprises melting crystalline sugar, contacting such sugar with gas at a pressure of 50 to 1,000 psig for a time sufficient to permit adsorption in said sugar of 0.5 to 15 ml of gas per gram of sugar, maintaining the temperature of said sugar during said adsorption above the solidification temperature of the melted sugar, and cooling said sugar under pressure to produce a solid amorphous sugar containing the gas.
The resultant product contains 1% to 5% water and most typically 2% to 3% water by weight of the total composition. Lower levels of moisture are not practicably obtainable because the additional heat necessary to drive off the water causes the candy melt to caramelize or burn, resulting in an off-flavor, undesirable product. Higher moisture levels result in a soft, sticky matrix which rapidly liberates the entrapped gas and is thus not storage stable. It has been found that the water activity of the product made according to the above patent is between about 0.10 to about 0.30. Additionally, the candy glass, in order to maintain storage stability, must be isolated from any source of free water and is thus packaged in a moisture-resistant container. Free water softens the candy allowing the trapped gas to escape.
The carbonated candy when placed in the mouth produces an entertaining but short lived popping sensation. As the candy is wetted in the mouth the candy melts and the carbon dioxide escapes. The effect in the mouth is sensational but short.
Conventional chewing gums are available in a variety of forms. The gum base may be any chewable substantially water insoluble base such as chicle and substitutes thereof, sorva, guttakay, jelutong, synthetic polymers such as polyvinyl acetate, synthetic resins, rubbers, mixtures of these and the like. The percentage of gum base employed in chewing gums may vary widely according to the type used and other ingredients employed and whether the final product is a "stick" chewing gum or a "bubble" gum or dragee. Minor amounts of plasticizers or softeners may also be incorporated in the gum base.
Flavors generally employed in the preparation of flavored chewing gums are the essential oils of synthetic flavorings used either singly or in combination with other natural and synthetic oils. Flavors such as wintergreen, spearmint, peppermint, birch, anise fruit flavors, mixtures thereof and the like may be used satisfactorily with a variety of gum bases. The amount of flavoring material used will vary depending on the type used, individual taste preferences, the gum base employed and other such considerations.
The sweetener or sweeteners added to complete the chewing gum composition categorize the gum as either a sugarless or a sugar gum. Sugar gum is intended to include not only sucrose but also the other sugarlike sweeteners normally employed in chewing gums such as dextrose, glucose (corn syrup), fructose and the like and mixtures thereof. Sugarless gums normally include synthetic sweetening agent such as saccharin or cyclamate or salts thereof and/or the dipeptide sweetening agents dihydrochalcones and the like or mixtures thereof combined with a sugar alcohol such as sorbitol and mannitol. Where the sugar alcohol has a sweetness intensity near sucrose, such as xylitol, then synthetic sweetener may be dispensed with.
The gums are conventionally prepared by mixing heated chewing gum base and sweetening agents such as sucrose as an aqueous sugar syrup or in the case of sugarless chewing gums an aqueous sugar alcohol solution plasticizers and flavor. These aqueous solutions typically contain 15% to 70% water. The resultant product contains from 1% to 5% by weight of moisture. Such moisture levels are required to render conventional gum pliable. At lower moisture the gum becomes hard and brittle. Additionally, in order to preserve the moisture content of the gum, each piece is enveloped with at least one protective wrapper.
The water activity of conventional chewing gums is typically about 0.35 to about 0.60. The sugar and sugar alcohols in conventional chewing gum remain crystalline in form. Thus, the moisture content of conventional gum exists essentially as free water, being absorbed on the surface of sugar or sugar alcohol crystals. This is contrasted with the moisture existing in amorphous carbonated candy which is bound within the structure and has a substantially lower water activity.
When conventional chewing gum containing 1-5% water contacts or is packaged with carbonated candy, the water migrates from the gum to the candy and the candy becomes sticky and loses its characteristic pop and sizzle while at the same time the gum becomes hard and stale.
U.S. Pat. No. 3,262,784 (Fleer) discloses a low moisture chewing gum. Such a gum is a crumbly friable material and resembles sand or powdered sugar at room temperature. The crystalline sugar component has a low moisture content well below 1%. The gum base is dry. While the Fleer patent discloses gum base proportions to 40%, the bubble gum is usually between abot 5% to about 27% for sugar alcohol gums and 6% to 25% when sucrose is used.